The true story that inspired the new drama Conviction is one of undying devotion and unchangeable belief. In the film, actress Hilary Swank portrays Massachusetts mother Betty Anne Waters and her eighteen-year journey to free her imprisoned older brother “Kenny” — played by actor Sam Rockwell.

In 1983, Ken Waters was sentenced to life in prison for the first-degree murder of an Ayer, Massachusetts woman. There were no witnesses to the violent crime, so Waters’ conviction was primarily based on court testimony from two of his ex-girlfriends — both of whom testified they heard him speak in detail about the murder.

Waters’ younger sister Betty Anne believed from the start that he was wrongly accused, convicted and imprisoned. She decided to become a lawyer in order to free her brother. To accomplish that goal, Waters earned her GED, then a Bachelor’s degree, and eventually a law degree from Rogers Williams University in nearby Rhode Island — all while waitressing and bartending to make ends meet after her marriage ended in divorce.

Last month at the Toronto International Film Festival, where Conviction had its world premiere, Betty Anne and director Tony Goldwyn stopped by the AMC News studio to talk about Waters’ incredible journey to exonerate her brother and bring her story to the big screen.